U.S. patent application Ser. No. 11/483,008 filed on Jul. 6, 2006 and entitled “Capacitance Sensing Electrode with Integrated I/O Mechanism” (incorporated by reference herein in its entirety) teaches capacitance based touch sensing. U.S. patent application Ser. No. 11/649,998 filed on Jan. 3, 2007 and entitled “Proximity and Multi-Touch Sensor Detection and Demodulation” (also incorporated by reference herein in its entirety) teaches a multi-touch sensing panel which can be combined with a display in a portable device. U.S. Provisional Patent Application Ser. Nos. 60/804,361 and 60/883,979, both entitled “Touch Screen Liquid Crystal Display” (and both incorporated by reference herein in their entireties), show earlier designs for combining a multi-touch panels with display panels.
It can be advantageous for a multi-touch panel to be combined with a display to form an integrated multi-touch display panel. Such a display panel can provide an intuitive interface to many types of devices.
Existing schemes to combine a multi-touch panel with a display can involve mounting a transparent multi-touch panel on top of a display. Alternatively, some existing systems can provide for a higher level of integration, wherein some layers of the multi-touch panel can also act as layers of a display. However, these systems can require that the circuitry performing touch sensing be placed in different layers than circuitry associated with the display functionality. This can result in relatively expensive systems. Furthermore, the brightness of the display can be decreased, as the multi-touch related layers are usually not completely transparent.